[refulgentis]

This is true: i.e. they use rare metals not rare earth metals.

On HN, I hope we can share a correction like that respectfully: after all, they gave good info, except for a one-word slip of the tongue.

The critique seems to extend beyond correcting that error, becoming confrontational, questioning motivation and honesty with phrases like "supposedly worked in." and the long bit defending lifespan and enviromental impact against people who "don't seem to have a problem with oil drilling, fracking, coal strip mining, etc" - they didn't even touch on that subject.

[beanjuice]

Thank you for responding, I agree with your points, I did indeed make a mistake.

[pfdietz]

Which rare metals do they use? Silver for contact wires? If silver supplies were inadequate (they're not) these could be substituted for with copper, if a barrier layer was included between it and the silicon.

[gradschoolfail]

Maybe indium in ITO for those fancy transparent front contacts. Or tellurium in CdTe, supposedly still costeffective compared to “thick” Si cells. I would still give GGP a break it can be tricky to venture even small steps outside ones specialty these days

[pfdietz]

And, maybe in the future, gallium as a dopant in silicon cells, since it doesn't experience nearly as much light induced degradation as boron does. But dopants are used in very small amounts.

I think some power electronics uses europium silicide (or was that erbium?) as a gate material, so maybe in inverters? Again, the quantities would be small.